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Old 01-22-2013, 03:33 PM   #51 (permalink)
christofoo
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Join Date: Mar 2012
Location: Salt Lake City
Posts: 292

00C - '00 Toyota Corolla
90 day: 43.54 mpg (US)
Thanks: 147
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I agree with Daox on economics. Mine consumes about .75 kWh in 2 hours to give me a 50-60 degree F delta, or $0.06 per use at $0.075/kWh. The benefits include several stops and EOC's for me, since without the block heater I need the engine on all the time to prevent frost, so I would throw out 25 mpg vs 40 mpg for the first mile as a guestimate (probably not too far off), which works out to .015 gallons, or about $0.06. There might be some additional savings for a few miles after that, but not much (for me). EDIT: suppose it's 18 mpg without the heater, a number I think I've seen the Civic's SGII report for that first mile with the engine on, then it's 0.031 gallons or $0.11 in gas per plugin.

EDIT: not including wear-and-tear, my ROI would be 800 plugins for a $40 install, or about 10 years if I assume 5 days a week and the season is 1/3 of the year. For a $140 install that would be 2800 plugins or 35 years. Then again, it's really difficult to calculate something like this with much confidence.

For me the primary benefit is smog emissions, but it also should be expected to reduce wear-and-tear. My heater is only 400 W (360-380W in real life), so it doesn't actually get the engine warm enough to heat the cab right away, although I get warmth in about 5 miles vs about 10 without.

I think that hood insulation has some similar benefits at a lower cost, depending on daytime highs and driving patterns. I'm still putting this one off though, for no reason.

Quote:
Originally Posted by pete c View Post
that 3 mpg increase is quite good. i suspect you have a fairly short commute. i can't imagine it being that much if you have a longer drive.

how difficult is the install on a typical vehicle?
I wrote a tutorial for my old Corolla, although I believe several cars are similar. http://ecomodder.com/forum/showthrea...9-a-23864.html

EDIT: Here's a thread featuring a recirculating engine block heater: http://ecomodder.com/forum/showthrea...6-a-24259.html Here's another freeze-plug version, in a Civic but almost the same as my installation I think: http://ecomodder.com/forum/showthrea...stall-765.html


Last edited by christofoo; 01-22-2013 at 05:58 PM..
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